According to an official press release, on 22 August 2013, the Bank of Mauritius issued new 25-, 50-, and 500-rupee banknotes printed on polymer. The 25- and 50-rupee notes were printed by Oberthur Technologies on Innovia Security's Guardian substrate, whereas the 500-rupee note was printed on De La Rue’sSafeguard substrate (formerly called Flexycoin). The new polymer notes will circulate in parallel with the preceding paper banknotes upon which their designs are based. The notes contain numerous new security features such as transparent windows showing the image of the dodo, numbers printed with magnetic ink which become fluorescent under ultra violet light, and swing features printed in iridescent ink, which change to a different color when observed in transparency or when tilted.